The Best Smart Thermostats for 2025

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A smart thermostat can help you save a considerable chunk of money by reducing your heating and cooling costs while allowing for convenient app and voice controls. However, not all smart thermostats are equally capable; some that work with simple heating and cooling systems just offer basic scheduling and programming options, while others that support complex multi-stage systems can control heating, cooling, dehumidifier, and ventilation systems. At PCMag, we have been reviewing smart thermostats for more than a decade, since the original Nest Learning Thermostat debuted in 2012. Our top pick, the Ecobee Smart Thermostat Premium, not only controls your heating and cooling but also serves as a voice assistant, an air quality monitor, and a home security device. It isn't the only model we recommend, however, so read on for plenty of alternatives for every budget.

How to Choose a Smart Thermostat

Smart thermostats offer various features that can not only help keep your home comfortable but also reduce heating and cooling costs. The most basic models are relatively inexpensive but still have Wi-Fi radios that allow you to connect the device to your home network and the internet. You can control them remotely from a mobile device and sometimes even from a web browser.

Basic controls allow you to raise and lower the temperature, create a seven-day heating and cooling schedule, override the schedule if you or a family member plans to return home early or late and turn the system on and off. The Nest Learning Thermostat takes scheduling a step further; it can create a heating and cooling schedule based on when you are usually home or away, factoring in what temperature you prefer during those times.

As is usually the case, you get more features if you pay more. A bright, colorful touch display makes it easy to configure and program the thermostat and gives it a touch of style—these types of screens are also usually legible from across a room. Moderately priced thermostats don't usually display the current time and temperature until you tap the screen, but more expensive devices use motion sensors to turn on their displays automatically when you enter the room.

Many of the latest smart thermostats contain humidity sensors that notify you of high or low humidity levels, and some models even show your local weather forecast. The Ecobee Smart Thermostat Premium comes with a remote room sensor that helps keep temperatures uniform throughout your house, especially in rooms that are far away from the thermostat.

If you want your thermostat to automatically lower the temperature when you leave your house and kick back on when you arrive home, look for a model that supports geofencing technology, such as the Nest Thermostat. Geofencing uses your phone's location services to let the thermostat know when you have entered or exited a virtual perimeter around the house. You can set your preferred Home and Away temperatures via a companion app. Then the thermostat will work to achieve those numbers once it detects you entering or leaving the perimeter. Just make sure you have your phone with you when you leave the house.

Usage reporting is another helpful feature that lets you see historical data on how often your system is running and how long it takes to meet its target temperature. Some thermostats even tell you what the outside temperature was at the time so you can see how it impacted your HVAC system. Other common features to look for include reminders for maintenance and air filter replacements, vacation scheduling capabilities, and power cycle alerts that let you know if your system is acting erratically.

What Else Do Smart Thermostats Work With?

If you have other smart devices in your home, look for a thermostat that works with as many of them as possible. The Nest Learning Thermostat works with other Nest devices, as well as numerous third-party devices, including smart switches, fans, and lighting systems. IFTTT support is a popular feature that allows you to configure the thermostat to trigger other compatible devices and services (or vice versa). For example, you can create an applet that turns on a smart air conditioner when your thermostat reaches a certain temperature. Matter is another emerging standard to look out for, as it promises to unite the IoT ecosystem across brands and standards.

Many of the latest smart thermostats support Amazon Alexa, Apple Siri, and Google Assistant voice commands. That means you can change temperature settings and find out the current temperature simply by speaking. Some of the most feature-rich smart thermostats have built-in Alexa voice control and can do just about everything that a smart speaker does; you can ask them to play music, get the latest news and sports scores, find out the weather forecast, change temperature settings, and much more.

Can You Install a Smart Thermostat Yourself?

Smart thermostats are usually easy to install, but it's important to know how your system is wired before you begin. Always make note of your wiring before you remove your old thermostat, and if possible, take a picture. Most of the latest devices come with pre-printed labels that you can attach to the wires to help identify them during the installation. You should also know what type of system you have as that often comes up during setup. Common HVAC system types include gas, oil, electric, propane, forced air, and radiant.

Most smart thermostats work with multi-stage heating and cooling systems, but if you plan to control other components such as whole-house dehumidifiers, heat pumps, and ventilation systems, make sure you select a model that supports those devices. In fact, if you have a complex multi-component HVAC system, it's a good idea to have a professional HVAC technician install the thermostat for you to avoid damage to your system.

Another factor to consider is whether your system contains a C (common) wire, which supplies constant power to the thermostat. Almost all smart thermostats require a C wire to work, but older houses with older heating systems usually don't have one because older thermostats do not require one. Some smart thermostats come with a power extender kit that you can install yourself to supply power to the device. Other devices, including Nest thermostats, can be installed without a C wire but steal power from the furnace control circuits to provide enough power to keep the internal battery charged. Although this method usually works without issue, it still might cause problems with certain HVAC systems and might actually cycle on the system to steal power. If you prefer not to take a chance on frying your furnace's circuit boards, hire a professional technician to run a C wire for around $150 or so.

Between installation and the device itself, a smart thermostat can cost a significant premium over a traditional model. But keep in mind that it can save you money on heating and cooling costs over time, not to mention the flexibility it provides when you're both in and out of the house.